But you reject any answer other than one somewhere roughly around 6000 years ago. And why might that be? Could it be because rather than looking at the evidence you're making an assumption of inerrancy about your interpretation of a story from a 2000 year old book written by desert nomads?

Genetic fallacy. Even if my belief in the Bible would be the only reason for me rejecting an answer, it wouldn't be I would be wrong for doing so.(although it would probably ignorant and stupid on my part)

If I'm wrong about this last part then all you need do is explain why Parsons estimate of mitochondrial mutation rates should be used in making the calculation for Mit-Eve.

Because it is an actual real-time measurement of the rate. It's operational science. This reason should favor the pedigree based approach.

The phylogeny based approach really only gives us a prediction of what the Theory of Evolution says the rate should be. What happens when you go and actually measure what the rate is, and it comes out to be not at all what the theory predicted ? Should you still trust the phylogeny-based rate ??

Of course, such an answer would be surprising in the extreme. It would require a great deal of research to explain how it fits with all the archeological evidence of human habitation much older than 6000 years, and with what we know of human migration rates and the fact that there was no land connection between Asia and the Americas after about 10,000 years ago. How could anyone who lived a mere 6000 years ago be a common ancestor of all modern people in both the old and new worlds?

The creationists litterature seems filled with how all this can be interpreted in a coherent framework. But I agree that such dating of mit.-Eve seems unreconciliable with the current evolutionnary-paradigm of human history.

If you did, and that was the only data that you had to go on, you would conclude that the most recent time that all humans (not including neandertals) could have a common female ancestor is very unlikely to be less than 10,000 years ago, and therefore, with that as the only data, the earth is very unlikely to be less than 10,000 years old.

slevesque writes:

The phylogeny based approach really only gives us a prediction of what the Theory of Evolution says the rate should be. What happens when you go and actually measure what the rate is, and it comes out to be not at all what the theory predicted ? Should you still trust the phylogeny-based rate ??

There are problems with the actual rate of occurrence as a long term measurement. If all the mutations are neutral, then about half would drift out in the long term. If some are slightly disadvantageous, then those would be liable to negative selection in the long term.

Then there's the problem of hotspots, which means that mutations could reverse back and forth amongst other things. Then there's the problem that, on rare occasions, a woman might have a slightly advantageous mutation that wiped out others in an area (becomes fixed in a region).

All of these would push the "most recent" date further back.

But even if all mutations survived, the data from that paper would certainly not lead you to believe that humans are only 6,300 years old, and went through a bottleneck 4,300 years ago.

There's also DNA data on regional stone age people compared to the modern inhabitants that would blow out that view.

So, slevesque, ask yourself why it is that you find the Parsons' survey alone on some creationist sites, and not the other much larger survey that I've linked to.

Is it the sin of lying by omission?

The title of this thread is, ironically, secularists do not want the truth.

If I'm wrong about this last part then all you need do is explain why Parsons estimate of mitochondrial mutation rates should be used in making the calculation for Mit-Eve.

Because it is an actual real-time measurement of the rate. It's operational science. This reason should favor the pedigree based approach.

The phylogeny based approach really only gives us a prediction of what the Theory of Evolution says the rate should be. What happens when you go and actually measure what the rate is, and it comes out to be not at all what the theory predicted ? Should you still trust the phylogeny-based rate ??

You should try to understand why the two approaches differ instead of ceasing your investigation as soon as you find a study you like. As bluegenes explains in Message 78, a larger study using the same approach as Parsons' found a lower rate. And as he also explains, much work has been done explain the discrepancy, and we now understand that factors like drift and mutational hotspots and so on are important factors that cause the rate to measure higher when performed on a tiny number of contemporary generations.

So if it really isn't a case of you just liking the 6000 year date better, explain why Parson's value should be accepted, given the additional information that has been provided to you.

This month's issue of American Scientist magazine has an article about the evolution of penguins in Antarctica: Evolution on a Frozen Continent (looks like you need a subscription if you want more than the abstract, sorry). Nesting grounds contain preserved biological material going back more than 40,000 years. The mutation rates can be measured very precisely and are consistent with widely accepted mutation rates in other species.

But I agree that such dating of mit.-Eve seems unreconciliable with the current evolutionnary-paradigm of human history.

If no-one had ever heard of evolution and everyone believed in fiat creation of species it would still be irreconcilable with archaeology. It's not the ToE that tells us when (for example) Australia was colonized, and there'd be nothing incompatible with the ToE if it had happened last week instead.

So, did you read the paper I linked to above? Message 73Larger survey on mtDNA mutation rates with discussion including Parsons' data.If you did, and that was the only data that you had to go on, you would conclude that the most recent time that all humans (not including neandertals) could have a common female ancestor is very unlikely to be less than 10,000 years ago, and therefore, with that as the only data, the earth is very unlikely to be less than 10,000 years old.

Sorry, I didn't miss your post but didn't really have the time to read through that paper since I'm in the middle of moving back to montreal for school.

I skimmed through it though, but found no reference to the minimum 10k age you are referring to. In your previous post, you said you calculated a 15k mininum a couple years back, is those two references one and the same ?

There are problems with the actual rate of occurrence as a long term measurement. If all the mutations are neutral, then about half would drift out in the long term. If some are slightly disadvantageous, then those would be liable to negative selection in the long term.

Then there's the problem of hotspots, which means that mutations could reverse back and forth amongst other things. Then there's the problem that, on rare occasions, a woman might have a slightly advantageous mutation that wiped out others in an area (becomes fixed in a region).

the paper says this in it's conclusion:

quote:We have argued that several of the explanations posited for a systematic difference between phylogenetic and pedigree estimates of mutation rates are more limited than they might ﬁrst appear to be. Pedigree estimates of this mutation rate are unbiased, regardless of the heterogeneity in rates—or of mutational hot spots—in the CR.

Doesn't this a bit contradict your claim on plausible explanations of the difference between pedigree and phylogeny-based estimates ?

But even if all mutations survived, the data from that paper would certainly not lead you to believe that humans are only 6,300 years old, and went through a bottleneck 4,300 years ago.

Which as a reference to the paper, but claims (if you read the relevant part of the article) that this paper in fact supports an age of 6500 years old.

I'm not a geneticist, like you seem to be, so maybe you could enlighten me on how you calculated your minimum age and how Dr. Dewitt could have gotten his 6,5k figure.

There's also DNA data on regional stone age people compared to the modern inhabitants that would blow out that view.

You talking about Neanderthals ?

So, slevesque, ask yourself why it is that you find the Parsons' survey alone on some creationist sites, and not the other much larger survey that I've linked to.

Is it the sin of lying by omission? The title of this thread is, ironically, secularists do not want the truth.

As shown above, the paper you've linked can be found on this creationist site, along with references to other surveys of the pedigree approach and also to papers for the phylogeny based approach.

And also, the paper in itself does not give any date. The date you talk about is your own calculation from their data. Dewitt seems to have calculated a different date from the same data. How can I know who's right ?

You should try to understand why the two approaches differ instead of ceasing your investigation as soon as you find a study you like.

where in this discussion have you gotten the impression I had ceased my investigation ?

As bluegenes explains in Message 78, a larger study using the same approach as Parsons' found a lower rate.

But it also didn't include heteroplasmy in their calculation of the mutation rate (unlike Parsons) so if I understand this correctly it's normal that they found a lower rate, while not meaning that any age calculated from the two different rate would be different. (Purely intuitively, this may explain the difference from the Bluegene age and the Dewitt age if one of the two didn't include this particularity of the Sigurđardottir paper)

And as he also explains, much work has been done explain the discrepancy, and we now understand that factors like drift and mutational hotspots and so on are important factors that cause the rate to measure higher when performed on a tiny number of contemporary generations.

This may turn out to be an unfounded claim as per my quote from the paper's conclusion, which says mutational hotspots have no effect (if I'm reading it correctly)

So if it really isn't a case of you just liking the 6000 year date better, explain why Parson's value should be accepted, given the additional information that has been provided to you.

It isn't really Parsons value I favor. It's the whole pedigree approach in general. Me simply refering to the Parson paper earlier in the discussion doesn't mean I'm focusing solely on their numbers.

This month's issue of American Scientist magazine has an article about the evolution of penguins in Antarctica: Evolution on a Frozen Continent (looks like you need a subscription if you want more than the abstract, sorry). Nesting grounds contain preserved biological material going back more than 40,000 years. The mutation rates can be measured very precisely and are consistent with widely accepted mutation rates in other species.

I skimmed through it though, but found no reference to the minimum 10k age you are referring to. In your previous post, you said you calculated a 15k mininum a couple years back, is those two references one and the same ?

Those figures are from me. In the discussion, they put the figure for the four surveys (including Parsons') combined at 14 mutations for 1221 transmission events. Worked out relative to Parsons' time estimate, this gives you 15, 800 yrs.

The Icelandic survey on its own will give you a whopping 42,300 yrs.

sleve writes:

the paper says this in it's conclusion:

"We have argued that several of the explanations posited for a systematic difference between phylogenetic and pedigree estimates of mutation rates are more limited than they might ﬁrst appear to be. Pedigree estimates of this mutation rate are unbiased, regardless of the heterogeneity in rates—or of mutational hot spots—in the CR."

Doesn't this a bit contradict your claim on plausible explanations of the difference between pedigree and phylogeny-based estimates ?

No. What they're saying is that pedigree estimates are unbiased in determining the mutation rate, with which I agree.

But if you go on and read the rest carefully, you can see that they agree that the rate is unlikely to be a good indicator of what remains in the population long term, because of heterogeneity, which they say "undoubtedly exists".

For my purposes here, that doesn't matter, in the sense that we're talking about what the minimum age of the mtDNA Eve could be without considering the factors like heterogeneity, selection and drift (which would all make her older).

In other words, I'm rigging it to your advantage as a YEC, and pointing out that if those surveys were the only data you had to go on, because of the 15,800yr figure, you would say that the earth is very unlikely to be less than 10,000 yrs old, because that would require a 37% margin of error in your favour.

Which as a reference to the paper, but claims (if you read the relevant part of the article) that this paper in fact supports an age of 6500 years old.

I'm not a geneticist, like you seem to be, so maybe you could enlighten me on how you calculated your minimum age and how Dr. Dewitt could have gotten his 6,5k figure.

You're making my point for me here. Dr. DeWitt says:

quote:A number of studies have demonstrated a remarkable similarity in the nuclear DNA and mtDNA among modern humans. In fact, the DNA sequences for all people are so similar that scientists generally conclude that there is a ‘recent single origin for modern humans, with general replacement of archaic populations.’8 To be fair, the estimates for a date of a ‘most recent common ancestor’ (MRCA) by evolutionists has this ‘recent single origin’ about 100,000–200,000 years ago, which is not recent by creationist standards. These estimates have been based on comparisons with chimpanzees and the assumption of a chimp/human common ancestor approximately 5 million years ago. In contrast, studies that have used pedigrees or generational mtDNA comparisons (6), (9), (10) have yielded a much more recent MRCA—even 6,500 years!(10).

He lists three papers, but that's all he says about them, and the "even 6,500 years" can only be passing reference to the Parsons paper, yet he misleadingly puts the (10) reference after it! Sin of omission. He could have done some maths, and said "from 6,500 years to 42,325 years". He also omits to mention heterogeneity, selection possibilities etc.

He appears to know his audience. They won't look at details, and won't understand what's going on.

sleve writes:

bluegenes writes:

There's also DNA data on regional stone age people compared to the modern inhabitants that would blow out that view.

You talking about Neanderthals ?

No. I mean us. If you're one of the YECs who considers Neanderthals to be descendents of Adam and Eve, then the sequencing of their DNA is an even bigger problem for you, as it would put the age of the earth way back, even at the Parsons mutation rate.

What I was referring to is samples of DNA taken from specimens like the oldest complete skeleton found on this island (9,200 years by our dating, but for you, he must be post-flood).

There are people in this region today in the same specific mtDNA haplogroup. Not much change. But a big change from people in the middle-east, and ancient skeletons in North America, for example.

sleve writes:

The date you talk about is your own calculation from their data. Dewitt seems to have calculated a different date from the same data. How can I know who's right ?

My main point with regard to Parsons was that we want to understand the discrepancy between various measurement approaches before reaching any conclusions. Without that understanding any choice is likely to be flawed.

As I mentioned earlier, archaeology and human migration patterns are your other big problem with a near-term date, and these factors have nothing to do with evolution.

slevesque writes:

How did they get their 40k years figure ?

Radiometric dating and the counting of annual nesting layers. Some nesting areas went back some 40,000 years, others only a few thousand years.